The criteria that have been used for many years in the design of wood aircraft structures are based on the assumption of a moisture content of 15 percent in wood parts.
Are hard knots acceptable in aircraft quality wood?
Are hard knots acceptable in a piece of aircraft quality wood? Hard knots unacceptable. … In laminated wood all of the grains run in the same direction, in plywood the grain in the layers cross the others at a 90 degree or 45 degree angle.
What type of wood is considered the reference wood for aircraft?
Woods Used in Aircraft Construction There are four woods, which are regularly used for aircraft construction. These are Sitka spruce, birch, ash and Douglas fir.
What are the most common wood materials used in aircraft construction?
Spruce is the preferred choice and the standard by which the other wood is measured. Figure 6-10 provides a comparison of other wood that may be suitable for aircraft repair. It lists the strength and characteristics of the wood in comparison to spruce.
What wood is superior for aircraft and is used as the standard for all woods?
1. Which species of wood is considered to be the standard when comparing other woods for use in aircraft structure? Sitka spruce.
What type of wood is made by gluing together two or more layers of wood?
Plywood and laminated wood are both made of layers (laminae) of wood glued together. The basic difference is that in plywood the grain of alternate layers is crossed, in general at right angles, whereas in laminated wood it is parallel.
What are the three configurations of wood used in aircraft structures?
There are different types of woods used in aviation: Solid wood, laminated wood, and plywood.
Why is spruce used in aircraft?
Common uses and applications
Sitka spruce is used to make a variety of structural products. Because it is stronger than the same weight component made of steel, Sitka spruce is used to build airplane framework components. It has virtually no odour or taste so is suitable for food storage and processing.
Which glue is acceptable for wooden aircraft repair?
Resorcinol is the only known adhesive recommended and approved for use in wooden aircraft structure and fully meets necessary strength and durability requirements. Resorcinol adhesive (resorcinol-formaldehyde resin) is a two-part synthetic resin adhesive consisting of resin and a hardener.
Why are bushings made of plastic or light metal used on wooden structures?
Why are lightweight steel bushings sometimes used in wooden structures? Bushings prevent the wood from being crushed when bolts are tightened.
Why is balsa wood used for model making?
Because it is so light and easily cut with a craft knife, it is perfect for making model aircraft or for whittling. Because this wood has a lower density than cork it is put to use in other applications where its low density is useful – for example as the core in many surfboards, or in the blades of wind-turbines.
What is bonding process in aircraft wood structure?
The term bonding, as applied to composites, is used to describe a common method for joining composite structures. Bonding is the process in which previously manufactured component parts are attached together during assembly of the airplane. Bonding composites can also be compared to welding metal.
Is balsa wood considered as soft wood?
For instance, yew wood is classified as a softwood but is considerably tougher than certain hardwoods. Likewise, balsa wood is classified as a hardwood and yet it’s one of the least dense and softest types of wood.
What is the term used for the discoloration or softening of the wood?
Decay may be evident as either a discoloration or a softening of the wood. … The term is actually a misnomer for any decay, since all fungi require considerable moisture for growth.
How can rot be revealed during an inspection of a wood structure?
A sharp metal tool is used to probe the suspected area. If the area is firm that’s what is desired. If it feels mushy or soft the wood has rotted and it is necessary to disassemble the structure for any repair or replacement needed.
Which of the following woods are considered soft woods?
Examples of hardwood trees include alder, balsa, beech, hickory, mahogany, maple, oak, teak, and walnut. Examples of softwood trees are cedar, Douglas fir, juniper, pine, redwood, spruce, and yew. Most hardwoods have a higher density than most softwoods. Most softwoods have a lower density than most hardwoods.